1. Field of the Invention
The present invention relates to a system or device for immobilizing a reinforcing tube in a flexible apron of a handling door for an industrial building.
2. Discussion of Background Information
This kind of door generally comprises a metal structure made up of a drive shaft and several horizontal reinforcing bars or reinforcing tubes which are housed, via sheaths, in the thickness of the flexible apron or curtain.
The horizontal reinforcing bars or reinforcing tubes slide in vertical slideways fixed on the vertical and opposed uprights of the handling door.
The vertical guiding slideways have a separation which is significantly greater than the width of the curtain so as to allow it to move from an open position to a closed position.
In the lower part of the flexible apron or curtain of the door and parallel to the horizontal reinforcing bars there is a hauling bar which is connected to the drive shaft by way of hauling straps which wind onto the drive shaft.
Some horizontal reinforcing bars or reinforcing tubes bear connecting or guiding means which are formed as flexible devices as described, for example, in French patent FR 98 14301 (2 785 639) in the name of the Applicant, the disclosure of which is expressly incorporated by reference in its entirety.
These flexible connecting devices are designed to connect the hauling or safety straps freely to the corresponding horizontal reinforcing bars or reinforcing tubes to allow the flexible apron or curtain of the handling door to be raised evenly.
To fit the flexible connecting devices, it is noted that housings or openings are cut from the thickness of the sheaths of the flexible apron or curtain in the region of the corresponding horizontal reinforcing bars.
The flexible connecting devices are identical in their configuration however many horizontal reinforcing bars there are, that is to say that the same flexible connecting device is found on the horizontal reinforcing bar situated at the bottom of the curtain as on the horizontal reinforcing bar placed at the top of the curtain.
Thus, the hauling strap, when the door is in the open position, lifts the hauling bar which, as it travels upward, comes into contact with the horizontal reinforcing bar just above it to drive it vertically and so on up to the horizontal reinforcing bar situated at the top of the curtain.
In the door-raising movement, the widths of the curtain which are situated between two horizontal reinforcing bars fold and stack up on one another to form a concertina of fabric.
Horizontal tubes or breaker tubes which may or may not be free with respect to the hauling strap may be inserted between the horizontal reinforcing bars. The function of the breaker tubes is to form and maintain the fold of the curtain between two contiguous horizontal reinforcing bars while the door is in its opening movement.
When the flexible curtain moves vertically, it is found that the horizontal reinforcing bars may slide within the sheaths, damaging the ends thereof when these are closed.
It is also found that the ends of the horizontal reinforcing bars may emerge from the sheaths of the flexible apron or curtain and rub on and damage the vertical walls of the guiding slideways and of the vertical uprights of the handling door.